RE: [PATCH 2/5] ACPI / debugger: Fix regressions that AML debugger stops working

From: Zheng, Lv
Date: Tue Jul 05 2016 - 22:08:35 EST


Hi, Rafael

> From: rjwysocki@xxxxxxxxx [mailto:rjwysocki@xxxxxxxxx] On Behalf Of
> Rafael J. Wysocki
> Subject: Re: [PATCH 2/5] ACPI / debugger: Fix regressions that AML
> debugger stops working
>
> On Tue, Jul 5, 2016 at 1:18 PM, Lv Zheng <lv.zheng@xxxxxxxxx> wrote:
> > The FIFO unlocking mechanism in acpi_dbg has been messed up by the
> > following commit:
> > Commit: 287980e49ffc0f6d911601e7e352a812ed27768e
> > Subject: remove lots of IS_ERR_VALUE abuses
> > It converts !IS_ERR_VALUE(ret) into !ret. This patch fixes the
> > regression.
> >
> > Fixes: 287980e49ffc ("remove lots of IS_ERR_VALUE abuses")
> > Signed-off-by: Lv Zheng <lv.zheng@xxxxxxxxx>
> > Cc: Arnd Bergmann <arnd@xxxxxxxx>
>
> OK, but ->
>
> > ---
> > drivers/acpi/acpi_dbg.c | 6 ++++--
> > 1 file changed, 4 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/acpi/acpi_dbg.c b/drivers/acpi/acpi_dbg.c
> > index 1f41284..ebc8d18 100644
> > --- a/drivers/acpi/acpi_dbg.c
> > +++ b/drivers/acpi/acpi_dbg.c
> > @@ -602,7 +602,8 @@ static int acpi_aml_read_user(char __user *buf,
> int len)
> > crc->tail = (crc->tail + n) & (ACPI_AML_BUF_SIZE - 1);
> > ret = n;
> > out:
> > - acpi_aml_unlock_fifo(ACPI_AML_OUT_USER, !ret);
> > + acpi_aml_unlock_fifo(ACPI_AML_OUT_USER,
> > + ret < 0 ? false : true);
>
> -> The ternary operation is not necessary here, because the result of
> (ret < 0) is already boolean. So this can be written as
>
> acpi_aml_unlock_fifo(ACPI_AML_OUT_USER, ret >= 0);
>
> and analogously below.
>
> I've made that change, please check the result in bleeding-edge.

[Lv Zheng]
Confirmed to be working.
Thanks for the simplification.

Thanks and best regards
-Lv